Improvement in tools for boring holes



A. ELIAERS.

TOOL FOR BORING HOLES.

No. 46,483 Patented Deo. 20, 1864.

UNITED STATES PATENT OFFICE.

AUeUsTUs ELIAERS, OF BOSTON, MASSACHUSETTS.

IMPROVEMENT l-N TOOLS FOR BORING HOLES.

Specification forming part of Letters Patent No. 45,483. dated December20, 1864.

To all whom it may concern:

Be it known that I, AUeUsrUs ELrAnns', of Boston, in the county ofSuffolk and State of Massachusetts,-have invented certain new and usefulImprovements in Tools for Formin g Apertures, &c.; and I do herebydeclare that the following description, taken in connection with theaccompanying plate of drawing hereinafter referred to, forms a full andexact specification of the same, wherein 1 have set forth the nature andprinciples of my said improvements whereby my invention may bedistinguished from all others of a similar class, together with suchparts as I claim and desire to have secured to me by Letters Patent.

The object of my invention is to so construct a cutting-tool thatapertures of greater diameter at the bottom than at the top, orundercuts, can be formed, and yet allow the cutter to be withdrawn. Toform such undercut holes is especially desirable for the insertion ofrubber or other elastic studs or buttons, which are firmly held therein.

My improved cutting-tool is represented in the accompanying drawings, ofwhich Figure 1 is a central vertical section of cutter adapted to theforming of grooves or undercuts on the exterior of any surface, and Fig.2 a side elevation of the same. Figs. 3 and4 are similar views showingmy improved levereutter as adapted to the forming undercut apertureswithin a body of wood or other material.

' ea in Figs.3 and 4 represent a hollow or s'otted shaft or rod havinginserted within it a lever-cutter, b b, turning upon a pivot at 0, itsupper end forming two cams, (Z and 6. Upon the periphery of the shaft ora is cut a small screw, f, upon which works a nut, g, attached to orforming a part of an arm or handle, h. A bent screw, 1', presses.against the cam e of thelever-cutter 11 Zn The screw-shafta a turns uponacen'ter, is.

From the foregoing description it will be seen that the cutting scope ofthe lever'cutter b b, as it turns upon a pivot, 12, can be increased ordiminished at pleasure by turning the arm or handle h up or down, thenut g of the said arm acting upon the cam d of the lever-cutter b b, soas to throw its cutting-edge farther f1 um its center- It, while the armor handle it is being turned up and the spring 6 retracting or throwingthe cutter in, when the nut g is relieved. from the cam d. Thus thelength of radius of the cutting-edge of the lever b b can becontinuously increased, so as to form an undercut while operating byscrewing the nut g upward upon the screw-shaft a a, and then the toolwithdrawn by' simply unscrewing the said not, the bent spring i drawingthe lever-cutter in, as will readily be understood.

' In Figs. 1 and 2 my improvements are rep resented as applied to thepurpose of forming grooves or undercuts' mion exterior surfaces. l l isthe screw-shaft, having a h-ollpw socket, 112, at one end to tit overthematerial to be cut and turning upon a center, at. o o is the levercutterturning upon a pivot, 11, and operated upon at one end by a cam-shapednut, q, that can be screwed up and down upon the screwshaft 1 l by meansof a handle, 1'. s is a bent spring'that throws the lever-cutter outwhen it is to be withdrawn.

It will be seen that by turning the nut q downward the cutting-edge ofthe lever-cutter will be pressed inward, and by turning it upward, so asto relieve its bearing upon the lever-cutter, the bent spring 8 willdraw it away from its center, the whole operation of the tool beingsubstantially the same as that represented in Figs. 3 and 4.

Having thus described my improvements, what I claim as my invent-ion,and:- desire to have secured to me by Letters Patent, is

A lever-cutter attached to or working within a serewshaft, and sooperated upon by a nut and spring, or their equivalents, that the lengthof its radius from the center of said screw-shaft can be increased ordiminished at pleasure while being revolved,for the purpose of formingundercuts, substantially as described.

ATE. 'ELI E ns.

